Net Investment Income Tax in 2026: Who Owes the 3.8% Surtax

Watch: Net Investment Income Tax explained with examples

The video above covers the essentials. The sections below go deeper on the numbers, the paperwork and how coverage is used to pay the bill.

A client sells a rental property and books a six-figure long-term capital gain. He expects to pay 15% or 20% on it. Then his advisor mentions an extra 3.8% federal tax that most people never plan for. That extra 3.8% is the net investment income tax, usually shortened to NIIT, and in 2026 it still catches retirees, business owners and high earners off guard because it is not part of the ordinary income tax brackets at all.

This guide explains how the tax works, which income it reaches, how the IRS calculates it on Form 8960, and how permanent life insurance is often used to hold cash that is not exposed to it. If you are within striking distance of the income thresholds below, the planning conversation is worth having well before December.

What the Net Investment Income Tax Actually Is

The net investment income tax is a 3.8% surtax created by the Affordable Care Act in 2010 and written into the Internal Revenue Code as section 1411. It is not a payroll tax, it is not withheld from your paycheck, and it does not appear as a separate bracket on your Form 1040. Instead, it is computed on a separate return, IRS Form 8960, and reported on Schedule 2 of your 1040 as part of other taxes.

The tax applies to the lesser of two numbers: your net investment income for the year, or the amount by which your modified adjusted gross income exceeds the statutory threshold for your filing status. That “lesser of” rule is the single most misunderstood piece of the whole calculation. Crossing the threshold does not tax your entire investment income, and having large investment income does not trigger the tax if your MAGI stays below the threshold.

2026 NIIT Income Thresholds by Filing Status

The thresholds are fixed in statute and are not indexed for inflation, which means more households cross them every year even without a raise in real terms.

Modified adjusted gross income for this purpose is adjusted gross income with certain foreign earned income exclusions added back. For the overwhelming majority of taxpayers it is the same as AGI. That is also why the calculation is best left to a tax professional when foreign income, foreign housing exclusions or controlled foreign corporations are in play.

What Counts as Net Investment Income

Form 8960 walks through the categories line by line. Investment income generally includes everything earned by assets outside a retirement account:

• Taxable interest from bank accounts, corporate bonds and taxable municipal bonds
• Dividends, including most ordinary and qualified dividends
• Capital gains from selling stocks, bonds, mutual funds, real estate and other appreciated property
• Rental and royalty income, whether or not you materially participate
• Gains from the sale of non-qualified annuities
• Income from a trade or business in which you do not materially participate, known as passive activity income
• Net gains from trading in commodities, options and certain financial instruments

Just as important is what the surtax does not touch. Wages, self-employment income, Social Security benefits, unemployment compensation and distributions from IRAs, 401(k)s and other qualified retirement plans are excluded from net investment income. That exclusion is the reason the tax can surprise a retiree who has always lived on W-2 wages and then sells a lifetime of appreciated stock in a single year.

Three Examples of How the Surtax Really Works

The math is easier to trust with numbers. Consider a married couple, Charlie and Nancy, in three different years.

In the first scenario the couple is $150,000 over the $250,000 joint threshold, so $150,000 of their $400,000 in gains is exposed to the extra 3.8%. In the second, they are $100,000 over the threshold, but only $50,000 of that is investment income, so only $50,000 is taxed. In the third, a smaller capital gain with a smaller excess means only $30,000 is exposed. The lesson is that the tax is capped by whichever figure is smaller, and that ordinary working income is never part of the base.

How the 3.8% Changes Effective Capital Gains Rates

Brokers quote long-term capital gains rates of 0%, 15% and 20%. Once NIIT is layered on, high earners are effectively looking at a top rate near 23.8% on long-term gains and up to 40.8% on short-term gains taxed at ordinary rates. State income tax can push the combined number past 30% in states like California or New York.

1. Calculate your projected AGI before year end, not in April.
2. Identify which gains, dividends, rents and interest would be exposed to the 3.8%.
3. Look for ways to spread a large one-time gain across two tax years where the transaction allows it.
4. Consider assets whose growth is not counted as investment income at all, such as cash value inside a permanent life insurance policy.
5. Review installment sales, charitable remainder trusts and qualified opportunity zone deferrals with a CPA before signing a sale contract.

Why Life Insurance Shows Up in NIIT Planning

Life insurance is not a loophole and it does not erase the surtax, but it does hold money in a wrapper where the annual build-up is not treated as investment income. Inside a whole life or indexed universal life policy, cash value grows on a tax-deferred basis. As long as the policy stays in force and the withdrawal or loan rules are respected, policy owners can access cash value through loans and withdrawals without creating the interest, dividend or capital gain income that Form 8960 is built to capture.

Three features explain why planners use it with clients who are chronically above the thresholds:

• Tax-deferred cash value growth that does not generate a Form 1099-INT, 1099-DIV or 1099-B each year
• An income-tax-free death benefit under section 101(a) that can replace wealth spent on estate taxes or charitable gifts
• Policy loans that are generally not taxable income while the policy remains in force and is not a modified endowment contract

The death benefit is also what makes an irrevocable life insurance trust such a common companion to charitable and estate plans. If a large charitable gift removes assets from the estate, the trust restores liquidity to the family. If you want to see how that works alongside retirement income planning, our guides to life insurance in retirement planning and life insurance versus a 401(k) walk through the trade-offs.

Common Mistakes That Trigger an Unexpected 3.8%

Most NIIT surprises come from four planning gaps.

1. Assuming retirement means low taxes. Retirees living on portfolio sales often have higher MAGI than they did while working.
2. Ignoring Roth conversions. A conversion adds to AGI and can push you over the threshold, which is why conversion years deserve a full projection.
3. Selling appreciated assets in one lump. An installment sale or a charitable remainder trust can spread income and reduce the exposed base.
4. Forgetting state tax. Some states add their own tax on the same gain, and a few impose their own version of a surtax on high earners.

Related tax questions tend to arrive together. If you inherited an account, review the required minimum distribution rules and the treatment of a spousal IRA rollover before the tax year closes. If an estate is in the picture, our overview of estate and inheritance tax explains how the pieces interact.

Frequently Asked Questions

Is the 3.8% net investment income tax the same as the Medicare tax?

They were introduced by the same law and share the same thresholds, but they are separate. The Additional Medicare Tax of 0.9% applies to earned wages above the thresholds and appears on Form 8959. The net investment income tax applies to investment income and appears on Form 8960.

Does the NIIT apply to money in a 401(k) or IRA?

No. Distributions from qualified retirement plans are excluded from net investment income, although they still count toward AGI and can push your MAGI over the threshold so that other investment income becomes exposed.

Can I be over the threshold and still owe no NIIT?

Yes. The tax applies to the lesser of net investment income or the excess MAGI. A single filer with $250,000 of wages and $500 of bank interest owes the 3.8% only on the $500 of interest.

Is the death benefit from life insurance subject to the net investment income tax?

No. A death benefit paid to a beneficiary is generally excluded from income under section 101(a) and is not investment income. Interest earned on a delayed death benefit payment may be taxable, so settlement options deserve a look before they are selected.

Does selling a rental property always trigger the surtax?

Not always. The gain is included in net investment income, but the tax applies only to the portion of that gain that fits within the lesser-of calculation. A passive loss carryforward, an installment sale or a like-kind exchange can change the outcome dramatically.

Where do I report the tax?

You report it on Form 8960 and carry the result to Schedule 2 of Form 1040. Estimated tax payments usually need to be increased in the year a large gain is realized to avoid an underpayment penalty.

Related Resources

• IRS: Net Investment Income Tax
• IRS: About Form 8960, Net Investment Income Tax
• NAIC Consumer Insurance Resources
• Life insurance beneficiary guide
• Estate planning checklist

Get a Personalized Quote Before Year End

If your AGI is near $200,000 single or $250,000 joint, the window to act is before December 31, not April 15. Compare permanent and term life insurance quotes from our network of carriers, then review the illustration with your CPA so the cash value, the death benefit and the surtax thresholds are all working in the same direction. Start your free quote comparison now.